Arianna Huffington and Mika Brzezinski’s jamboree for “redefining success beyond money and power” was a victim of its own success, drawing 300 guests who squeezed into Huffington’s Mercer Street apartment yesterday. One guest who came to hear speakers including Valerie Jarrett, Joanna Coles, Katie Couric and George Stephanopoulos said La Huff’s place “could fit about 100, but there were three times as many people.” Another, who said she was “sweating and about to faint in an overflow room,” reports, “We had to use other apartments in the building to go to the bathroom, waiters were trying to squeeze through the crowd to offer tiny canapés and I couldn’t see the speakers.”